Dyestuffs



Patented Jan. 30, 1945 UNITED STATES PATENT OFFICE DYESTUFFS John David Kendall, Ilford, England, assignor to Ilford Limited, Ilford, England,

a British com- No Drawing. Original application August 8, 1936, Serial No. 95,033, now Patent No. 2,307,049, dated January 5, 1943. Divided and this application August 15,

1941, Serial No. 407,053.

In Great Britain August 16, 1935 10 Claims.

This invention relates to the production of dyestuffs.

It is an object of this invention to produce compounds comprising two heterocyclic nitrogen nuclei linked by a chain of atoms including one or more nitrogen atoms.

According to the process of the present inven- D tion, dyestuffs are obtained by condensing a quaternary salt of a heterocyclic nitrogen compound having a reactive thio-ether or selenoether group or a reactive amino-vinyl, ,acylamino-vinyl, aryl-amino-vinyl, or acyl-arylamino-vinyl grouping in the a or 7 position to a nitrogen atom with an organic compound containing two amino groups linked by a single bond or by a conjugate chain of carbon atoms some or all of which form part of one or more aromatic carbo-cyclic rings, and which may be represented by the general formula where n is 0 or a positive integer, or salts of such compounds.

Examples of such compounds are:

hydrazine, H2N-NH2 the 0- and p-arylene diamines such as oand p-phenylene-diamines HzNONHz benzidine and its homologues such as dianisidine diamino-stilbenes such as 2:2-, 2:4-, and 4:4- diamino-stilbene's, e. g.

The reaction may be carried out in the presence of a solvent with or without an acid binding agent. When an acid binding agent is required, e. g. when using salts of these compounds, the reaction may be carried out in a neutral solvent such as alcohol together with an acid binding agent such as sodium ethoxide or sodium acetate, or it may be carried out in the presence of a basicsolvent such as pyridine which acts as the acid binding agent.

The heterocyclic nitrogen compound whose BK ZOHaSH Many of the products of the present invention are coloured and are sensitisers for photographic silver halide emulsions. The dyestufls obtained by the reaction of quaternary salts of heterocyclic nitrogen compounds having reactive aminovinyl or substituted aminovinyl groups with organic compounds such as hydrazine which may be represented by the formula where n is or a positive integer are particularly good sensitisers, and the present invention includes a photographic silver halide emulsion sensitised with such a dyestuff.

One or more of the dyestuffs may be incorporated in the photographic silver halide emulsion before it is coated on a support, or alternatively the support (e. g. a film or plate) coated with the emulsion may be bathed in a solution of one or more of the dyestuffs. The actual quantity incorporated may vary to a certain extent with the individual dyestufi and with the ultimate effect which it is desired to obtain; as an indication, however, of the order of the quantities which may be employed, 100 cos. of a one in one thousand solution of the dyestufl' may be incorporated in six and a half litres of emulsion equivalent to about 250 grams of silver nitrate, or the coated support may be bathed in a one in one thousand solution of the dyestuff; the strength of the solution may vary according to the dyestuff used and may be as low as one in ten thousand.

The process of the present invention is illustrated by the following specific examples.

Example 1 5.43 gms. of 1-methylmercapto-benzthiozole and 5.58 gms. of methyl-p-toluene sulphonate were fused together for four hours at 130-140" C. 1.56 gms. of hydrazine-hydrochloride and 50 ccs. of pyridine were then added and the mixture boiled for half an hour. Crystals formed in the solution even when hot. The solution was poured into cold water, when a heavy precipitate of almost colourless crystals was formed. These were collected and washed and re-crystallised. The purified crystals melted at 257 C. The corresponding ethyl compound, was formed in similar manner, place of methyl-p-toluene sulphonate and was obtained as colourless crystals melting at 192 C.

Example 2 6.03 gms. of 1 ethylmercapto-quinoline, and 5.58 gms. of methyl-p-toluene sulphonate were heated together for four hours at 130-140 C. when the solid quaternary salt was formed. 1.6 gms. of hydrazine-hydrochloride and 30 ccs. of pyridine were then added and the whole maintained at. a temperature just below the boiling point for about half-an-hour. The mixture was then poured into water and the red crystals which formed were filtered off, washed with water and spirit and ether and dried and recrystallised from methyl alcohol as scarlet plates,

melting at 258 C. The corresponding ethyl compound, was prepared in a similar manner but using ethyl-p-toluene sulphonate in place of methyl-p-toluene sulphonate and formed scarlet needles and rods melting at 194 C.

Example 3 4.95 gms. of 1-methylmercapto-benzoxazole and 5.58 gms. of methyl-p-toluene sulphonate using ethyl-p-toluene sulphonate in were heated together at 130-140" C. for four hours. 1.6 gms. of hydrazine-hydrochloride and cos. of pyridine were then added and the whole mixture boiled for half-an-hour. The mixture was then poured into cold water and a precipitate of fine white crystals was formed. These were collected, washed and dried and the melting point was found to be 277 C.

Example 4 1.78 gms. of dimethylthiolthio-(fip')-diazole and 1.88 gms. of methyl-p-toluene sulphonate were heated together for 3 hours at 120-130 C. After cooling 0.6 gm. of hydrazine hydrochloride and 12 ccs. of pyridine were added and the mixture was gently warmed until solution was effected, after which it was gently boiled under a reflux condenser for half-an-hour. The mixture was then poured into 200 ccs. of water, when light coloured crystals separated out. These were collected and washed and re-crystallised from methyl alcohol to yield light yellow places melting at 170-172 C.

Example 5 1.78 gms. of dimethylthiolthio-(afi')-diazole and 1.88 gms. of methyl-p-toluene sulphonate were heated together for 3 /2 hours at 120-130 C. The mixture was allowed to cool and 0.6 gm. of hydrazine hydrochloride and 12 ccs. of pyridine were then added and the whole was gently warmed until solution was effected, after which the mixture was gently boiled under a reflux condenser for half-an-hour. The mixture was then poured into 200 ccs. of water, when whitish crystals separated out. These were collected and washed and re-crystallised from benzene to yield almost colourless plates melting at 282-3 C.

Example 6 1.76 gms. of 4-methylthiolquinazoline and 1.86 gms. of methyl-p-toluene sulphonate were heated together at -140 C. for four hours. gm. of hydrazine dihydrochloride and 25 ccs. of

, pyridine were then added and the mixture was gently warmed until the solid was dissolved. The

mixture was then gently boiled under a reflux condenser for half an hour after which it was poured into water and allowed to stand. The yellow solid which separated out was collected, washed and re-ciystallised to give bright yellow crystals melting at over 310 C.

Example 7 3.62 gms. of l-methylthiolbenzthiazole and 3.72 gms. of methyl-p-toluene sulphonate were heated together at l30140 C. for about 3%; hours. 1.08 gms. of o-phenylenediamine and 40 cos. of pyridine were then added and the mixture was gently heated until the solid was dissolved and then gently boiled under a reflux condenser for about 30 minutes. It was then poured into wa- After allowing this solution to stand until'cool' ter and allowed to stand when an oil separated out. This was separated off and extracted with boiling benzene. The benzene extract was cooled and a grey solid was precipitated from it, which was recrystallised from boiling benzene to yield an almost colourless solid, melting at 278 C.

I Example 9 3.62 gins. of l-methylthiol-benzthiazole and 3.72

gms. of methyl-p-toluene sulphonate were heated together at 130-140 C. for about 8% hours. 1.45 gms. of p-phenylenediamine dihydrochloride and 40 cos. of pyridin were then added and the mixture was gently warmed until all the solid was dissolved and was then gently 'bciled under a re flux condenser for about A; hour. A pale yellow solid began to form and the mixture was poured into water when a light yellow precipitate was formed. This was filtered off, collected and washed and extracted with hot benzene. The extract was cooled and the solid which formed, was recrystallised to give almost colourless crystals melting at 275 C.

Example 10 2.23 grams of 1:3t3-trimethyle2-w-acetanilido-. vinyl-indolenium iodide and 1.05 gins. of hydrazine hydrochloride were mixed with cos. of. pyridine. and the whole warmed on a water bath for about half an hour when an orange dye formed. The mixture was then gently boiled un-- der a reflux condenser for about twenty minutes. The liquid obtained was then poured into aque-' ous potassium iodide solution when the dye stuff was precipitated out as a crimson solid and recrystallised from methyl alcohol to give a dye which decomposed at about 250 C. Thi dye is. a very powerful sensitiser for silver chloride. emulsions and extends their sensitivity ranges to about 5900 A. with a fiat sensitising curve over the range from about 4600 A to about 5400 .5.

Example 11 112 grams of 1-w-acetanilido-vinyl-benzthiazole ethiodide, 4.5 grams of p-phenylenediamine hydrochloride were mixed together with 300 cos. of pyridine. The solids dissolved up and the solution became yellow in colour. The solution was then heated on a water bath for forty minutes. after which it was gently boiled under a reflux condenser for ten minutes, when a crimson eons separated out. The mixture was then poured into water and the crimson crystals which-separated out were filtered off, washed and dried. They melted at 285 C.

Example 13 21 grams of 1-w-acetanilido-vinyl-benzoxazole methiodide and 9.05 grams of paraphenylenediamine hydrochloride were mixed With 100 cos. of pyridine and gently boiled together. A deep yellow solution was obtained and orange coloured crystals were deposited from the hot solution.

the crystals were filtered washed and dried. They had a melting point higher than 305 C.

Example 14 112 grams of 1w-acetanilido-vinyl-benzthiazole ethiodide and 2.7 grams of hydrazine dihydrochloride weremixed together with 100 cos. of

. spirit and 4.1 grams of anhydrous sodium acetate.

On. gently warming the mixture at deep orange solution witha faint red tinge was obtained. This was diluted with water and brown crystals with a green reflex were deposited. These crystals were filtered ofi, washed and recrystallised from. methylaleohol and were iound to melt at 226 C. with decomposition.

Example 15 22.3 gramsof 1: 3': a-trimethylq-a-acetanilidovinyl-indolenium iodide, 9.2 grams of benzidine and 150 cos. of dry spirit were ently boiled together under a reflux condenser for minutes. The substances. dissolved in thespirit and then orange crystals with a. bluish reflex separated. from the. hot solution. After. cooling the solid,

was filtered off from the liquors and well washed with spirit and, ether. The crystals melted above 300 C. A further experiment showed that this reaction could be carried out equally well using pyridine in place of the alcohol.

Ezrample 16 22.5 grams of l-w-acetanilido-vinyl-'benzthiazolev ethiodide and 9.2 grams of. benzidine' were mixed. together with 200' cos. of dry spirit and the whole gently boiled for 30 minutes. A brown crystalline solid separated out, which wa filtered off. washed and dried and obtained as dark brown crystals melting at 260 C.

Example 17 21 grams of I-e-acetanilido-vinyl-benzoxazole methiodide and 9.2 grams of benzidine were mixed together with cos. of alcohol and the whole gently heated for a few minutes. An intense yellow solution was obtained from which small orange crystals separated out. These were filtered. oil and washed and dried and obtained as. orange yellow wder having a melting point above 300 C.

Example 18 18.1. grams of. l-methylthiol benzthiazole were heated together with 18.6 grams of methyl-ptoluene sulphonate for three and a half hours at 130440 C. 18.4 grams of benzidinev and 200 cos. of spirit were added and the mixture was gently warmed for twenty minutes when a light yellow solid was deposited and mercaptan evolved. The solid was filtered off, well washed with benzene, spirit and ether and obtained as almost colourless powder melting above 300 C.

Example 19 22.3 grams of 1:3:3-trimethy1-2-w-acetanilido-' vinyl indolenium iodide, 12.2 grams of di-anisidine (2:2'-dimethoxy benz'idine) and 100 ccs. of pyridine were mixed together and gently 'boiled under a reflux condenser for thirty minutes. A deep orange solution was obtained from which a brick red solid was deposited on cooling. This solid was filtered off, well washed and obtained as small brick red crystals, melting at 282 C. with decomposition.

This application is a division of copending application Ser. No. 95,033, filed August 8, 1936, now Patent No. 2,307,049, issued January 5, 1943.

What I claim is: r

l. A process for the production of dyestufls which comprises condensing by heating together a quaternary salt of a heterocyclic nitrogen compound of the type used in cyanine dyes which contains a grouping selected from the group consisting of the amino vinyl, acylamino vinyl, ary1-' amino Vinyl and acylarylamino vinyl groupings in a position selected from the group consisting of the a and 1 positions to the heterocyclic quaternary nitrogen atom with a second nitrogenous compound selected from the group consisting of diamine, diamines with two amino groups in which the two amino groups are separated by a chain of an even number not exceeding 10, of carbon atoms alternately doubly and singly bonded, the carbon atoms directly linked to the amino groups each forming with the next adjacent carbon atom in the chain part of a carbocyclic nucleus.

2. A process for the production of dyestufis which comprises condensing by heating together a quaternary salt of a heterocyclic nitrogen compound of the type used in cyanine dyes which contains a grouping selected from the group consisting of the aminovinyl, acylamino vinyl, arylamino vinyl and acylarylamino vinyl groupings in a position selected from the group consisting of the a and 7 positions to the heterocyclic quaternary nitrogen atom, with hydrazine in the presence of a solvent and acid binding substance.

3. A process for the production of dyestufis which comprises condensing by heating together a quaternary salt of a heterocyclic nitrogen compound of the type used in cyanine dyes which contains a grouping selected from the groupconsisting of the aminovinyl, acylamino-vinyl, arylamino vinyl and acylarylamino vinyl groupings in a position selected from the group consisting of the a and 7 positions to the heterocyclic quaternary nitrogen atom, with an arylene diamine in the presence of a solvent and acid binding substance.

4. A process for the production of dyestuifs which comprises condensing by heating together a quaternary salt of a heterocyclic nitrogen compound of the type used in cyanine dyes which contains a grouping selected from the group consisting of the aminovinyl, acylamino vinyl, arylamino vinyl and acylarylamino vinyl grouping in a position selected from the group consisting of the a and 7 positions to the heterocyclic quaternary nitrogen atom, with a polynuclear arylene diamine in the presence of a solvent and acid binding substance.

together in the presence of a solvent and an acid binding substance.

'7. A process for the production of a dyestufl comprising reacting 1: :3-trlmethyl 2 w-acetanilidovinyl indolenium iodide with benzidine by heating them together in the presence of a solvent and an acid binding substance.

8. A compound selected from the group consisting of dyestuffs of the general formula:

wherein D and D]. are the residues of heterocyclic nitrogen compounds of the type used in cyanine dyes, R. and R1 are alkyl groups and p is a positive integer not greater than 2 and the acid salts of such dyestufis.

9. A dyestuff of the formula:

which is a crimson solid melting and decomposing at about 250 C. giving an orange solution in alcohol and extending the sensitivity of silver chloride emulsions to about 5900 A. with a flat sensitizing curve over the range from about 4600 A. to about 5400 A.

h 10. A dyestuff of the formula:

which is in the form of brown crystals with a grem reflex giving an orange-red solution in alcohol, melting at 226 C. with decomposition and extending the sensitivity range of photographic silver halide emulsions.

JOHN DAVID KENDALL. 

